Systems, methods, and apparatus for communicating messages of distributed private networks over multiple public communication networks

ABSTRACT

Systems and methods for communicating messages of distributed private network (DPN) over a plurality of communication networks including an inter-network interface and a message coordinator communicatively coupled. The inter-network interface is operable to receive a packetized message from a first DPN network element over a first communication network. The message coordinator receives the packetized message from the inter-network interface, assigns at least a transport route for the packetized message; and communicates the packetized message to a second DPN network element based on the assigned transport route over a second communication network. The message coordinator is further operable to assign priority protocol and security protocol to the packetized message.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional PatentApplication No. 62/066,356 filed Oct. 20, 2014, which is in incorporatedherein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to the field of voice, data,and video communications and, more particularly, to system, method, andapparatus embodiments for facilitating the communication of packetizedmessages within or from distributed private networks over publiccommunication networks operated by corresponding communication serviceproviders.

BACKGROUND

Historically, communications infrastructure and transmission formatsutilized by electric grid operators have relied upon technologies thathave evolved as control systems have evolved. For example, analogcircuits that carried low bit rate packets and information could becarried over plain old telephone service (POTS), microwavecommunications, and physical links of various types that are known inthe art. Over time, both wireline and wireless infrastructure evolved todigital formats that have been the backbone for both privately owned,privately provisioned and public network infrastructures. These digitalformats, which are primarily synchronous networks and time divisionmultiplexed (TDM) networks, followed the analog modulation schemes byoffering greater capacity over both copper and wireless infrastructure.Such formats also lead to great innovations in speed and reliabilitywith the advent of the synchronous optical network (SONET), digitalwireless standards (such as, for example, the Global System for Mobilecommunications (GSM) and code division multiple access (CDMA)), framerelay protocols, asynchronous transfer mode (ATM) protocols, and manyproprietary methods for transporting information digitally. Such digitalformats have been beneficially employed to facilitate electrical gridoperations, including the overall function, registration, operation,command, control and participation of grid elements and their logicalcontrol infrastructure for grid stability and reliability.

In the last ten years, great strides have been made in thetelecommunications sectors through use of the Internet Protocol (IP)suite of transport and security protocols and the Open SystemsInterconnection (OSI) architecture. Similarly, advances in digitalswitching have reduced the amount of electronics and physical or virtualconnections and multiplexing required to enable use of more efficientasynchronous formats that incorporate various methods for increasing thespeed and reliability of IP transport connections. Ethernet connections,which heretofore were generally accepted only for local area network(LAN) connectivity, are now the standard for most data traffic,particularly for IP packets that do not require priority or security, orare for non-critical infrastructure.

More recently, the U.S. Federal Communications Commission (FCC) acceptedfilings of several telecommunications carriers, local exchange carriers(LECs), and local access and transport area (LATA) carriers (intra-LATAand inter-LATA carriers) who are authorized to transport voice or other“non-information” services traffic to convert the legacy POTS, analog,and synchronous digital (TDM) connections to an IP infrastructure forall connections within the carriers' service territories or FCC grantedlicensed areas if the carriers are also wireless service providers. Theprocess of conversion has been started in many carriers' core fiberinterconnections as the fiber cores have been converted from SONETnetworks to advanced high speed transport methods, such as MultiplePacket Label Switching (MPLS). Additionally, Signaling System No. 7(SS7) is being replaced by Session Initiation Protocol (SIP) as thecontrol protocol for setting up, maintaining, and tearing down voicecalls, especially over IP networks. The move to newer technologiesprovides many efficiencies for the carriers and facilitates a moredistributed infrastructure for both traditional voice services and datatransport services.

Further, FCC action in 2011 dealing with the interconnection of Dataover Cable Interface Specification (DOCSIS) for data transport in bothsynchronous and asynchronous formats of voice, video, and data withinfiber or hybrid fiber coax delivery systems and voice service commoncarriers over pure IP formats (voice-over-IP or “VoIP”), combined with(a) the rollout of third and fourth generation wireless infrastructure(including Long Term Evolution (LTE)) and the soon to be releasedTIA/IEEE standards for firth generation wireless services, and (b)advances in antenna design and software that have delivered advances inIEEE 802.11-X (a,b,d,g,n and its successors), have increased bit ratesthat take advantage of IP's inherent routing, reliability, andefficiency.

The FCC has recognized the movements by consumers and businesses to “cutthe cord” and use wireless phones as landline replacements, as well asto stop using analog and lower bit rate digital (e.g., TDM)technologies. As a result and unfortunately for traditional wirelinecommon carriers and LECs, the FCC, which has previously classified IPtraffic between carriers and Internet Service Providers as an“Information Service” not subject to Federal or State level PublicUtility Commission (PUC) oversight, has decided that federal rulesregarding VoIP traffic must be re-visited to consider whether the voicecomponent of the VoIP traffic is an “Information Service” or whether itconstitutes a service that is subject to new interconnection rulesbetween the carriers, the ISPs, the cable industry, the service-onlyproviders, and the wireless carriers.

There are many drivers for the FCC to take this action. For instance,under previous interconnection rules, carriers that interconnected theirvoice and or data traffic with each other did so through highlynegotiated interconnection agreements. Under these contracts and inaccordance with FCC requirements, each carrier from which trafficoriginated was compensated by the terminating carrier (wireless orwireline) for traffic terminated in the adjacent carrier's network. Atthe end of a pre-negotiated time frame, generally monthly, the totalsfor minutes of use, erlangs, or megabits (Mb) delivered were reconciledand inter-carrier compensation (ICC) was awarded to the net provider of“traffic” to the terminating carrier.

Furthermore, some of the charges that all carriers charge theircustomers on these legacy networks were taxes and fees to fund the buildout of rural telecommunications infrastructure. The “Universal ServiceFund” (USF) was set up for rural communities and their service providersto have access to federal grant money to fund rural deployments andupgrades with the goal of keeping rural America at the same level ofinnovation as urban areas. As the aforementioned transitions have takenplace, particularly with the introduction of IP transport for voice,video, and data, the fees flowing in the USF fund and, therefore, themoney available for grants to rural communities has been droppingdrastically for many years, forcing the FCC to re-evaluate itsdefinition of IP based voice services as subject to USF fees.

FIG. 1 provides one example of the typical interconnection of voice anddata traffic between two carriers (Wireline Carrier A and WirelineCarrier B, for example) providing wireline telecommunication services totheir respective service areas 101, 102. Each carrier includes arespective local access and transport area (LATA) switch 104, 107 (e.g.,a Class 4 tandem switch), as well as respective connection end point(CEP), billing, and call accounting functions 105, 108.

When a call originates in the service area 101 of Wireline Carrier A,which may be a large telephone or commercial carrier, and terminates inthe service area 102 of Wireline Carrier B, which may be a ruraltelephone cooperative or rural LEC, the LATA switch 104 for WirelineCarrier A establishes a circuit connection with the LATA switch 107 forWireline Carrier B. The voice call then proceeds over the establishedcircuit and the CEP/billing/call accounting function 105 for WirelineCarrier A bills for the call, including charging the required USF fee.Similarly, when a call originates in the service area 102 of WirelineCarrier B and terminates in the service area 101 of Wireline Carrier A,the LATA switch 107 for Wireline Carrier B establishes the circuitconnection with the LATA switch 104 for Wireline Carrier A. The voicecall then proceeds over the established circuit and the CEP/billing/callaccounting function 108 for Wireline Carrier B bills for the call,including charging the required USF fee. The two carriers would also beresponsible for paying each other ICC as required by the carriers'interconnection agreement. In situations such as those illustrated inFIG. 1, the periodic reconciliation between the large commercial carrierand the much smaller, rural carrier would typically result in the largercarrier (e.g., Wireline Carrier A in FIG. 1) paying the smaller carrierICC because, due to the much larger quantity of customers in the servicearea 101 of the larger carrier, more calls would likely originate fromthe larger carrier's network and terminate in the smaller carrier'snetwork than would originate from the smaller carrier's network andterminate in the larger carrier's network.

In 2012, the FCC issued an order requiring that ICC for VoIP was to nolonger be constrained by the definition of every packet that would orcould be transported by the Internet or IP infrastructure, whetherwireline or wireless, as an “Information Service.” The FCC furtherordered that all carriers must track VoIP separately from other dataservices for USF funding under a new so-called “bill and keep”methodology, wherein voice traffic, regardless of its origin and format,would be tracked from the originating network and be billed by thenetwork provider regardless if it is delivered to an adjacent network.In other words, under the FCC's “bill and keep” model, each carrier isrequired to terminate communications from another carrier for free. TheFCC's order also went further in providing that each carrier, regardlessof its type, would provide a defined “Point of Interface” (POI) wherecarriers could pass IP traffic (IP voice or data) from one networkboundary or carrier to the next.

An additional issue that has recently been resolved through litigationdeals with the concept of “net neutrality” or “open Internet.” In 2010,the FCC advised carriers that operated IP networks, Internet serviceproviders (ISPs), or any network providers that passed IP packets thatoffering “Priority Access,” which would take advantage of the IPprotocol's natural OSI protocols to order packets in the most importantorder as determined by the carrier and the application, would not bepermitted. The FCC's order was controversial as it allowed for pureapplications companies to utilize carrier networks to transportbandwidth intensive services regardless of their impact to the overallspeed, reliability, and capacity of the transport links. Companies thatoffer bandwidth intensive applications (e.g. music, video, or livestreaming) would have in effect, under “net neutral” protocols, the samepriority of transport as private and public entities providing criticalinfrastructure applications, such as emergency services, electrical gridoperations, potable water supply operations, and natural gas supplyoperations.

In response to the FCC's net neutrality requirement, grid operators,utilities, and market participants constructed private networks fortheir operations to insure that their traffic, carried either throughtheir own transport (wireless, fiber, copper etc.) or through transportleased from commercial carriers, had priority over being carried withinthe public or common carrier infrastructure. Where privateinfrastructure was used, additional cost was incurred by the privatenetwork operators for dark fiber, dedicated network capacity, privateradio networks, and leased lines, for example.

In 2013, a federal appeals court struck down the FCC's net neutralityrequirement after the FCC was sued by a combination of carriers. Thecourt affirmed the carriers' ability to define the uses of theirnetworks and charge, provision and allocate resources, includingpriority access, as the network carriers and providers saw fit, subjectto the FCC's requirements for differentiating and accounting for VoIP asa service for purposes of paying USF fees and subject to the FCC's “billand keep” model for carrier interconnection.

In view of the court's decision on net neutrality, network carriers havesought federal approval to decommission their legacy POTS, TDM, FrameRelay, ATM, SONET, and other networks in favor of using IP networks. Thelegacy networks have historically been used by electrical gridparticipants and users of other distributed private networks (e.g.,public safety networks). As a result, grid participants and otheraffected private network users will have to re-design their networks assecure IP networks before 2020.

With the movement of telecommunications carriers to IP transport and theability for the carriers to define new points of interface, a need hasarisen for new methods and apparatus to enable distributed privatenetworks, such as, for example, the electric power grid and othercritical infrastructure networks, to communicate messages over public IPnetworks while maintaining the security and priority requirements ofeach particular distributed private network.

SUMMARY

The present invention is directed to systems and methods forcommunicating messages of distributed private network (DPN) over aplurality of communication networks for critical infrastructure, thesystem comprises at least one of an inter-network interface and amessage coordinator. The inter-network interface comprises at least onenetwork interface, a processing function and a memory. The messagecoordinator comprises at least one network interface, a processingdevice and a memory. The inter-network interface is communicativelycoupled to the message coordinator. The inter-network interface isoperable to receive a packetized message from a first DPN networkelement over a first communication network. The message coordinator isoperable to receive the packetized message from the inter-networkinterface; assign at least a transport route for the packetized message;and communicate the packetized message to a second DPN network elementbased on the assigned transport route over a second communicationnetwork.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a PRIOR ART conventionalinterconnection between two telecommunications carriers.

FIG. 2 is a block diagram illustrating configuration of a system forcommunicating messages of one or more distributed private networks overmultiple public communication networks operated by correspondingcommunication service providers, in accordance with an exemplaryembodiment of the present disclosure.

FIG. 3 is a block diagram illustrating configuration of a system forcommunicating messages of one or more distributed private networks overmultiple public communication networks operated by correspondingcommunication service providers, in accordance with another exemplaryembodiment of the present disclosure.

FIG. 4 is an electrical block diagram illustrating essential andoptional components of an inter-network interface and a distributedprivate network (DPN) network element, in accordance with a furtherexemplary embodiment of the present disclosure.

FIG. 5 illustrates positioning within the Open System Interconnection(OSI) protocol stack of a messaging format from which an inter-networkinterface or a message coordinator may determine whether a receivedpacketized message is a message communicated within a distributedprivate network, in accordance with yet another exemplary embodiment ofthe present disclosure.

FIG. 6 is a flow diagram representing data flow between layers ofexemplary OSI protocol stacks executing within elements of a system forcommunicating messages of one or more distributed private networks overmultiple public communication networks, in accordance with a furtherexemplary embodiment of the present disclosure.

FIG. 7 is a logic flow diagram of steps executed by an inter-networkinterface to facilitate the communication of messages of one or moredistributed private networks over multiple public communicationnetworks, in accordance with another exemplary embodiment of the presentdisclosure.

FIG. 8 illustrates a logic flow diagram of steps executed by elements ofa system for communicating messages of one or more distributed privatenetworks over multiple public communication networks, in accordance witha further exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION

Systems and methods of the present invention provide for communicatingmessages or packets of a distributed private network (DPN) over aplurality of communication networks including an inter-network interfaceand a message coordinator communicatively coupled. The inter-networkinterface is operable to receive a packetized message from a first DPNnetwork element over a first communication network. The messagecoordinator receives the packetized message from the inter-networkinterface, assigns at least a transport route for the packetizedmessage; and communicates the packetized message to a second DPN networkelement based on the assigned transport route over a secondcommunication network. The message coordinator is further operable toassign priority protocol and security protocol to the packetizedmessage.

The present invention may further include elements of systems andmethods for messaging as described within U.S. patent application Ser.No. 13/563,535 filed Jul. 31, 2012 and published as US PatentPublication No. 2014/0039699 for “SYSTEM, METHOD, AND APPARATUS FORELECTRIC POWER GRID AND NETWORK MANAGEMENT OF GRID ELEMENTS,” and U.S.patent application Ser. No. 14/290,598 filed May 29, 2014 and publishedas US Patent Publication No. 2014/0277788 for “SYSTEM, METHOD, AND DATAPACKETS FOR MESSAGING FOR ELECTRIC POWER GRID ELEMENTS OVER A SECUREINTERNET PROTOCOL NETWORK,” both by inventor Forbes, Jr., which areincorporated herein by reference in their entirety.

According to one embodiment, a method is provided for communicatingmessages of one or more distributed private networks over a plurality ofpublic communication networks operated by a corresponding plurality ofcommunication service providers. The one or more distributed privatenetworks include network elements distributed throughout service areasof the public communication networks. According to this embodiment, aninter-network interface receives packetized messages from the public orprivate communication networks, wherein at least one of the receivedpacketized messages is directed to a network element of a distributedprivate network. The inter-network interface acts as a sole point ofdemarcation for interconnecting network elements of the distributedprivate network through the public communication networks. Theinter-network interface communicates the packetized message or messagesdirected to network elements of the distributed private network to amessage coordinator for the distributed private network. The messagecoordinator is operable to provide at least one of routing,prioritization, and security functions for the packetized messagescommunicated over the public or private communication networks tonetwork elements of the distributed private network. The messagecoordinator may form part of the inter-network interface, be co-locatedwith the inter-network interface, or may be communicatively coupled tothe inter-network interface, but located separate from the inter-networkinterface. Functions of the message coordinator are performed by one ormore of network elements of the distributed private network to effect adistributed message coordinator. The distributed private network may bea critical infrastructure network, such as, for example, a network forsupplying and delivering electricity (e.g., an electrical grid or anetwork of an entity that supplies power to, controls the distributionof power over, or maintains the stability and reliability of anelectrical grid), a network for supplying and delivering natural gas, anetwork for supplying and delivering potable water, a network used forproviding public safety services, a network used for providing local ornational security services, or a network used for communicatingemergency information.

In another embodiment, an inter-network interface is provided tofacilitate the communication of messages of distributed private networksover a plurality of public communication networks. The inter-networkinterface includes at least one network interface (which may be at leastone transceiver), memory, and a processing function. The inter-networkinterface functions as a sole point of demarcation for interconnectingthe distributed private networks through the communication networks, inparticular for public communication networks. The at least one networkinterface or transceiver transmits and receives packetized messages toand from the communication networks. The memory stores operatinginstructions and routing tables. The processing function is operable inaccordance with the stored operating instructions to: (a) receive fromthe at least one network interface transceiver packetized messages fromthe public communication networks, wherein at least one packetizedmessage is directed to a target network element of a distributed privatenetwork, and (b) communicate, via the at least one network interface ortransceiver and according to the routing tables, the packetized messageto a message coordinator for the distributed private network. Themessage coordinator is operable to provide routing, prioritization,and/or security functions for packetized messages communicated over thepublic communication networks to network elements of the distributedprivate network. The processing function is further operable inaccordance with the operating instructions to extract data from thepacketized message to produce extracted data; transform the extracteddata into transformed data usable by a first network element of thedistributed private network; and communicate via the at least onenetwork interface or at least one transceiver a secure packetizedmessage to the first network element based on one or more routingtables, security protocol, priority protocol. The secure packetizedmessage includes the transformed data.

In a further embodiment, a method is provided for communicating messagesof a distributed private network over a plurality of communicationnetworks operated by a corresponding plurality of communication serviceproviders. According to this embodiment, a message coordinator of thedistributed private network receives a packetized message from aninter-network interface controlled by a first communication serviceprovider or an independent private network message aggregator. Thepacketized message originated from a first network element of thedistributed private network. The network element that sent the messageis serviced by a first public communication network operated by a secondcommunication service provider. The message coordinator assigns at leasta transport route (and optionally a priority and/or a security protocol)for the packetized message, wherein the assigned transport routerequires the packetized message to be communicated over a second publiccommunication network operated by a third communication serviceprovider. The message coordinator communicates the packetized message tothe inter-network interface for further communication of the packetizedmessage to a second network element of the distributed private networkbased on the assigned transport route for the packetized message. Inthis case, the second network element, which is the intended target ofthe packetized message, may be located within a service area of thesecond public communication network.

In yet another embodiment, a system is provided for communicatingmessages of a distributed private network over a plurality of publiccommunication networks operated by a corresponding plurality ofcommunication service providers. According to this embodiment, thesystem includes an inter-network interface and a message coordinator.The inter-network interface functions as a sole point of demarcation forinterconnecting network elements of the distributed private networkthrough the communication networks. The inter-network interface isoperable to receive a packetized message from a communication networkoperated by a first communication service provider. The packetizedmessage is directed to at least a first network element of thedistributed private network. The message coordinator is communicativelycoupled to the inter-network interface and operable to receive thepacketized message from the inter-network interface. The messagecoordinator is further operable to provide at least one of routing,prioritization, and security functions for communicating the packetizedmessage to the first network element over one or more of the public orprivate communication networks.

In a further embodiment, a method is provided for communicating messagesof a distributed private network over public communication networksoperated by a corresponding set of communication service providers.According to this embodiment, an inter-network interface receives apacketized message from a public or private communication networkoperated by a first communication service provider (e.g., a smallercarrier, such as a rural LEC, a rural or lower class of service ISP, ora rural VoIP provider). The inter-network interface functions as a solepoint of demarcation for interconnecting the distributed private networkthrough the public communication networks. The inter-network interfacemay be controlled by a second communication service provider (e.g., alarge commercial carrier) or an independent private network messageaggregator. The packetized message is directed to at least a firstnetwork element of the distributed private network. The inter-networkinterface communicates the packetized message to a message coordinatorfor the distributed private network. The message coordinator may be asoftware function running on a processor used to implement some or allof the inter-network interface or may be software running on a processorof a separate hardware device (e.g., in a data center of the distributedprivate network or on a cloud server). Responsive to receiving thepacketized message, the message coordinator assigns a transport route(and optionally a priority and/or a security protocol) to the packetizedmessage to produce a route-assigned message. The message coordinatorthen communicates the route-assigned message to a packet router, whichmay be controlled by the second communication service provider or theindependent private network message aggregator. The packet router, whichmay also be implemented in software and run on a processor of theinter-network interface or the message coordinator, determines thetransport route (and optionally the priority and/or security protocol)from the route-assigned message and selects, based on the determinedtransport route (and priority and/or security protocol (when included inthe route-assigned packet)), a public communication network over whichto communicate the packetized message to the first network element ofthe distributed private network.

In a further embodiment, a method is provided for communicating messagesof a distributed private network over public communication networksoperated by a corresponding set of communication service providers.According to this embodiment, a first inter-network interface elementreceives a packetized message from a first public communication networkoperated by a first communication service provider. The firstinter-network interface element forms part of a multi-element,inter-network interface that is a sole point of demarcation forinterconnecting the distributed private network through the publiccommunication networks. The packetized message is directed to at least afirst network element of the distributed private network. The firstinter-network interface element communicates the packetized message to amessage coordinator for the distributed private network. The messagecoordinator assigns at least a transport route to the packetized messageto produce a route-assigned message and communicates the route-assignedmessage to a packet router. The packet router determines the transportroute for the packetized message from the route-assigned message andselects, based on the transport route, a second public communicationnetwork over which to communicate the packetized message to the firstnetwork element of the distributed private network. The second publiccommunication network is operated by a second communication serviceprovider and the first network element of the distributed privatenetwork receives communication service from the second publiccommunication network. After determining the transport route, the packetrouter communicates the packetized message to a second inter-networkinterface element that is coupled to the second public communicationnetwork. The second inter-network interface element also forms part ofthe multi-element, inter-network interface. The second inter-networkinterface element then communicates the packetized message to the secondpublic communication network for delivery to the first network elementof the distributed private network. The processing function is operableto determine a message coordinator to which to route a packetizedmessage based on a distributed private network that includes a networkelement to which the packetized message is directed; determine whether apreferred transport route is available for routing the packetizedmessage to the message coordinator; route the message to the messagecoordinator according to a preferred transport route when the preferredtransport route is available; and route the packetized message to themessage coordinator according to an alternative transport route thatincludes the second inter-network interface element when the preferredtransport route is unavailable.

In yet another embodiment, a network element is provided for use in adistributed private network that communicates packetized messages over aplurality of public communication networks. According to thisembodiment, the network element includes at least one network interfacetransceiver, memory, and a processing device or function. The at leastone network interface transceiver communicates packetized messages to aninter-network interface over a public communication network operated bya first communication service provider. The inter-network interface is asole point of demarcation for interconnecting the distributed privatenetwork through the public communication networks. The memory isoperable to store executable operating instructions for formatting thepacketized messages for communication within the distributed privatenetwork and applying a security protocol specified by the distributedprivate network. The processing device is operably coupled to the atleast one network interface or transceiver and the memory, and operablein accordance with the operating instructions to: (a) generate one ormore packetized messages directed to a target network element of thedistributed private network, (b) encrypt each packetized message basedon the security protocol to produce an encrypted message, and (c)communicate the encrypted message to the at least one network interfaceor transceiver. Each packetized message includes a messaging format usedin one or more lower protocol layers of the packetized message, whereinthe messaging format identifies the packetized message as being amessage communicated within the distributed private network.

Before describing in detail exemplary embodiments of systems, methods,and apparatus for communicating messages of distributed private networksover multiple public communication networks, one skilled in the artshould recognize that such embodiments may reside in combinations ofsystem and apparatus components and/or their operational software(including firmware, middleware, and applications). Accordingly, thesystems, apparatus, and method step components have been representedwhere appropriate by conventional symbols in the drawings, showing onlythose specific details that are pertinent to understanding the disclosedembodiments so as not to obscure the disclosure with details that willbe readily apparent to those of ordinary skill in the art having thebenefit of the description provided herein.

In this document, relational terms, such as “first” and “second,” “top”and “bottom,” and the like, may be used solely to distinguish one entityor element from another entity or element without necessarily requiringor implying any physical or logical relationship or order between suchentities or elements. The terms “comprises,” “comprising,” “includes,”“including,” “has,” “having,” contains,” “containing,” and any othervariations thereof are intended to cover a non-exclusive inclusion, suchthat a process, method, article, or apparatus that comprises, includes,has, or contains a list of elements does not include only thoseelements, but may include other elements not expressly listed orinherent to such process, method, article, or apparatus. The term“plurality of” as used in connection with any object or action means twoor more of such object or action. A claim element proceeded by thearticle “a” or “an” does not, without more constraints, preclude theexistence of additional identical elements in the process, method,article, or apparatus that includes the element.

As used herein and in the appended claims, “public communicationnetwork” means any wired, wireless, cable, satellite, optical, or othernetwork operated by a communication service provider that offers use ofthe network for a fee. Public communication networks include, but arenot limited to, Ethernet networks, circuit-switched telecommunicationsnetworks, packet-switched telecommunications networks, digitalsubscriber line (DSL) networks, voice-over-IP (VoIP) networks, CodeDivision Multiple Access (CDMA) networks, Global System for MobileCommunications (GSM) networks, Universal Mobile TelecommunicationsSystem (UMTS) networks, Enhanced Data Rates for GSM Evolution (EDGE)networks, networks that utilize third generation (3G) wireless dataprotocols, such as Evolution for Data Only (EVDO) and High Speed PacketAccess (HSPA), networks that utilize fourth generation (4G) wirelessdata protocols, such as Long Term Evolution (LTE), networks that utilizefifth generation (5G) networks that operate in accordance with the IEEE802.11 standard (WiFi networks) or any derivative standard approved bythe IEEE, International Telecommunications Union (ITU) or any domesticor international standards body, or networks that use proprietaryprotocols which can operate in real time or near real time and cansupport the transmission of packetized messages (e.g., Internet Protocol(IP) packets).

As also used herein, “distributed private network” means any non-publicnetwork that includes network elements distributed throughout theservice areas of two or more public communication networks and which usethe voice and/or data services of the public communications networks.Exemplary distributed private networks include, but are not limited to,critical infrastructure networks, such as networks for supplying anddelivering electricity, networks for supplying and delivering naturalgas, networks for supplying and delivering potable water, networks usedfor providing public safety services, networks used for providing localor national security services, and networks used for communicatingemergency information. Distributed private networks also includesubnetworks of larger composite networks. For example, an electricalgrid (a large composite distributed private network) may be composed ofmultiple subnetworks (e.g., smaller distributed private networksoperated by entities that supply power to the electrical grid, controluse and/or distribution of power from the electrical grid, and/ormaintain all or part of the electrical grid (e.g., independent systemoperators)). Where subnetworks are involved, each subnetwork may receivecommunication service from one or more of the public communicationnetworks.

As further used herein, “network element” means any hardware and/orsoftware module, process, or device which participates and/or functionsin a distributed private network. For example, but not by way oflimitation, a network element for an electrical grid may be a smartmeter, a substation controller, an Automatic Generation Control (AGC)process or subsystem, an Energy Management System (EMS), advancedmetering infrastructure (AMI) processes and subsystems, an advancedmeter reading (AMR) collector, or any other element, component, process,or device that transmits or receives grid-related data or information.

As also used herein, “message coordinator” means any hardware and/orsoftware module, process, or device that controls, manages, routes,prioritizes, and otherwise processes packetized messages communicatedbetween network elements of a distributed private network, and/ororiginates packetized messages for delivery to networks elements of thedistributed private network. Thus, a message coordinator does not merelyfunction as a traditional network layer router, but rather includesmessaging, management, and control functionality required for properlyfacilitating the exchange of packetized messages within a distributedprivate network according to the prioritization, routing, and securityrequirements of the distributed private network. Segmentation of thepacketized message complies with security requirements of thedistributed private network. The message coordinator may be implementedwithin a dedicated hardware device or may be implemented as a securecloud service.

The systems, methods, and apparatus of the present disclosure can bemore readily understood with reference to FIGS. 2-8, in which likereference numerals designate like items. The figures are provided forillustration purposes for embodiment illustrations and are not intendedto limit the invention thereto.

FIG. 2 is a block diagram illustrating a new high level architecture fora system that communicates messages of one or more distributed privatenetworks over multiple public communication networks operated byrespective communication service providers, in accordance with anexemplary embodiment of the present disclosure. The system architectureillustrated in FIG. 2 includes one or more inter-network interfaces, oneor more message coordinators 223 (one shown for illustration purposes),and a packet router 205 (which may form part of the inter-networkinterface or be controlled by an entity that controls the inter-networkinterface). According to one embodiment of this new architecture, eachinter-network interface is a sole point of demarcation forinterconnecting network elements 219-221 of a distributed privatenetwork through the public communication networks. In other words, alldistributed private network traffic flows through an inter-networkinterface to a message coordinator 223 for the particular distributedprivate network (DPN). In this manner, appropriate prioritization,security, and/or routing of DPN messages can be handled appropriatelyaccording to the specific requirements of the particular distributedprivate network. According to an exemplary embodiment, the inter-networkinterface may be provided or controlled by a host communication serviceprovider (e.g., Service Provider A as shown in FIG. 2), a third party,such as an independent private network message aggregator.

In the embodiment illustrated in FIG. 2, the inter-network interface(INI) includes multiple elements 211, 215 distributed within the serviceareas 201-203 of some or all of the public communication networks. Inservice area 201, the packet router 205 may include and/or serve as theINI element for that service area 201. Alternatively, the inter-networkinterface may be a single device positioned in the service area of apublic communication network. The inter-network interface interconnectsnetwork elements 219-221 of a distributed private network through thepublic communication networks. The inter-network interface may includeone or more points of interface (POIs) and/or may support multipleindependent and dedicated subnetworks to facilitate the efficientcommunication of DPN messaging based on prioritization and securityrequirements of the particular supported distributed private networks.For example, each distributed private network may be assigned to its ownsubnetwork for processing by the inter-network interface. Additionally,each distributed private network may include its own message coordinator223 or message coordinator function. Where the inter-network interfaceis controlled by a host communication service provider, such as a largecommercial carrier, the host provider may distribute and install the INIelements 211, 215 at boundaries of the service areas 202, 203 of theother public communication networks and at such other location as may beappropriate, such as at locations of fixed critical infrastructure wherethe inter-network interface supports packetized messages of a criticalinfrastructure network.

The three public communication networks illustrated in FIG. 2 areoperated by three communication service providers (Service Provider A,Service Provider B, and Service Provider C). Each public communicationnetwork provides communication service to a corresponding service area201-203. Those of ordinary skill in the art will readily recognize andappreciate that the quantity of public communication networks andassociated service areas may be more or less than the quantity shown forillustration purposes in FIG. 2. The description provided below willfocus primarily on an exemplary embodiment in which a packet router 205and INI elements 211, 215 are positioned within service areas 201-203 ofthree public communication networks to illustrate the architecture andoperation of the disclosed systems, methods, and apparatus.

In FIG. 2, the service areas 201-203 of the public communicationnetworks are illustrated as being geographically disjoint or separate.However, the service areas 201-203 may alternatively overlap or overlayone another either wholly or partially. For example, a wireless publiccommunication network may overlap or overlay another wireless publiccommunication network or a wired (e.g., cable, DSL, fiber, etc.) publiccommunication network. The disclosed systems, methods, and apparatus maybe applied for communicating messages of one or more distributed privatenetworks over the public communication networks regardless of whether ornot the service areas 201-203 overlap.

The inter-network interface may include the message coordinator 223 orbe collocated therewith, or the two devices/functions may begeographically separate and communicatively coupled together over adedicated communication link. Alternatively, the function of the messagecoordinator 223 may be distributed within the packet router 205 and/orthe INI elements 211, 215 that support the distributed private networkin which the message coordinator 223 functions.

Further, the message coordinator block depicted in FIG. 2 is intended tobe a very general functional block and is not intended to suggest thatonly one message coordinator is to be used under the illustrated systemarchitecture. According to one embodiment, each distributed privatenetwork is managed by its own message coordinator or message coordinatorfunction, and multiple distributed private networks may simultaneouslyexist and communicate over the same set of public communicationnetworks. As a result, the message coordinator 223 represents all themessage coordinator functions that may be required to support theparticular quantity of distributed private networks operatingsimultaneously. To more easily handle the flows of packetized datamessages flowing within the various distributed private networks, eachdistributed private network may be assigned to a separate subnetwork orsubnet within the inter-network interface, where the subnet for aparticular distributed private network is then interconnected with themessage coordinator for that particular distributed private network.

According to the exemplary embodiment depicted in FIG. 2, the publiccommunication network operated by Service Provider A includes aCEP/billing/call accounting function 209 (including call accounting forVoIP or other digitized voice calls, where Service Provider A providesVoIP/digitized voice calling services) and, when the public networksupports VoIP calling services, a software (soft) switch 207 forinterconnecting VoIP calls to and from VoIP subscribers within thenetwork's service area 201. According to one embodiment, theCEP/billing/call accounting function 209 and the softswitch 207 arecommunicatively coupled to a packet router 205 (which may incorporate anINI element as discussed above). The packet router 205 exchangespacketized messages with network elements 219 of one or more distributedprivate networks using the communication resources of the publiccommunication network so long as the DPN network elements 219 arelocated within Service Provider A's service area 201.

According to another embodiment, one or more DPN network elements219-221 may be transportable or mobile, if so permitted by theirrespective distributed private networks. In such a case, a transportableDPN network element 219 may register with the message coordinator 223for the distributed private network (or with the inter-network interfacethat includes the message coordinator function), via the packet router205 or another INI element, prior to receiving any DPN-relatedpacketized messages from the message coordinator 223. If thetransportable DPN network element 219 later moves into the service areaof another public communication network (e.g., from service area 201 toservice area 202), the DPN element 219 may re-register with the messagecoordinator 223 by sending a new registration message to the messagecoordinator 223 through the INI element 211 serving the new service area202. Upon receipt of the new registration message, the messagecoordinator 223 (or inter-network interface, as applicable) may changethe transport route and/or priority to appropriately route andprioritize packetized messages sent to the DPN network element 219 whileit is located within the new service area 202.

The public communication networks operated by Service Provider B andService Provider C may similarly include respective CEP/billing/callaccounting functions (not shown) and VoIP softswitches and/or foreignexchanges 213, 217 for interconnecting VoIP calls to or from VoIPsubscribers within each network's respective service area 202, 203.Alternatively, one service provider (e.g., Service Provider A) mayprovide VoIP call accounting for one or more other service providers andperiodically (e.g., monthly) report back to the billing systems of theother service providers the quantities, durations, and/or sizes of VoIPpacketized messages (VoIP packets) that passed through the inter-networkinterface during a predefined billing period so as to enable the otherservice providers to determine the amount of funds to be paid by them toa rural telephony assistance fund, such as the USF, if so required underapplicable communications regulations. For example, a large commercialcarrier (e.g., the carrier providing communication service in servicearea 201) may supply all the inter-network interface elements 211, 215and install them within the service areas 202-203 of the othercommunication service providers. Each INI element 211, 215 may includeone or more data POIs to support packetized data messages and one ormore VoIP POIs to support VoIP communications. The packetized datamessage communication is configured as a first independent subnetworksupported by the inter-network interface. The VoIP communicationservices are configured as a second independent subnetwork supported bythe inter-network interface. Each independent subnetwork has a physicallayer separate from every other independent subnetwork so as to providephysical, routable, and self-healing capabilities. The physical layerseparation is maintained by the packet router for each independentsubnetwork. Every month or at other predefined times, VoIP call data forVoIP calls passing through the VoIP POIs within the inter-networkinterface may be reported to the billing systems of Service Providers Band C to enable them to make their USF payments under, for example, theFCC's “bill and keep” model.

Where the inter-network interface is a multi-element interface with INIelements 211, 215 distributed throughout the service areas 201-203 ofthe public communication networks, each INI element 211, 215 or multipleINI elements may be located within a respective one of the service areas201-203. The INI elements 211, 215 may be communicatively coupledtogether such that packetized data links 225, 226 interconnect thepacket router 205 to the remote INI elements 211, 215. Additionally,where the inter-network interface supports VoIP or other digitized voiceservices, the VoIP-supporting portion or portions of each INI element211, 215 (e.g., VoIP POI) may be further coupled to the VoIP-supportingportion or portions of the packet router 205 through IP/VoIP trunks 229,230. Where VoIP service is supported, the packet router 205 and each INIelement 211, 217 may be coupled to a VoIP softswitch 207, 213, 217 forthe public communication network in which the packet router 205 or INIelement 211, 215 is located. The packet router 205 or the messagecoordinator 223 may use session initiation protocol (SIP) as theprotocol for processing and managing VoIP communications occurringthrough the inter-network interface.

Where the inter-network interface includes multiple INI elements 211,215, the INI elements 211, 215 may be configured in a hub-and-spokearchitecture, such that the packet router 205 or message coordinator 223serves as the hub through which all distributed private network andoptionally VoIP traffic flows. An exemplary hub-and-spoke architectureis illustrated in FIGS. 2 and 3, where optional data links 227 and VoIPtrunks 231 are excluded from the architecture of FIG. 2. Alternatively,the INI elements 211, 215 may be configured in a ring architecture toprovide enhanced reliability and redundancy in the event that apreferred link between any two INI elements is unavailable for anyreason. An exemplary ring architecture is illustrated in FIG. 2 whenoptional data links 227 and VoIP trunks 231 (if VoIP service issupported) are included in the architecture to interconnect INI element211 to INI element 215. By using a ring architecture for the INIelements 211, 215, if a data link or VoIP trunk between any two INIelements is unavailable for any reason, the data or VoIP packets may bere-routed through one or more of the other INI elements to maintainsystem performance. For example, when using a ring architecture forinterconnecting the INI elements 211, 215 to the packet router 205 (orthe message coordinator 223, for example, via the packet router 205), anINI element (e.g., INI element 211) may receive a packetized messagefrom a DPN network element 220 and determine whether a preferredcommunication path 225 between the INI element 211 and the messagecoordinator 223 is available for communicating the packetized message tothe message coordinator 223. If the preferred path 225 is available, theINI element 211 communicates (e.g., using a packetized messagingprotocol, such as TCP/IP) the packetized message to the messagecoordinator 223 via the preferred communication path 225. Alternatively,if the preferred communication path 225 is unavailable for any reason,the INI element 211 may be configured through software to communicatethe packetized message to the message coordinator 223 via an alternativecommunication path 227, 226, such as via one or more other INI elements215. A routing table may be stored in each INI element 211, 215 for usein determining an alternate path when the preferred communication pathbetween the INI element and the message coordinator 223 or packet router205 is unavailable.

The message coordinator 223 for a distributed private network may be aprocessor-based standalone device, a server instance or resource on ashared platform (e.g., such as a cloud server or set of cloud servers),or a software function or module operating as a process integrated intothe inter-network interface or the packet router 205. When integratedwith the inter-network interface, the message coordinator function maybe a centralized process (e.g., in a host server or a single INIelement) or be a distributed process running in multiple INI elements ofthe inter-network interface. In FIG. 2, the message coordinator 223 isillustrated in exemplary form as being either standalone or a functionmodule running within the packet router 205.

Some large-scale distributed private networks, such as electrical grids,may include several smaller distributed private networks that exchangedata, information, and operations messages with one another. To handlesuch cross-network message exchanges, the message coordinators 223 forthe smaller distributed private networks are configured to translate andappropriately route and prioritize messages received from onedistributed private network to another distributed private network,especially (although not exclusively) where the smaller distributedprivate networks effectively participate and function in a much largerdistributed private network. For example, a DPN element of a firstdistributed private network (e.g., an EMS system of a first electricutility) may submit a request or provide information (e.g., through anInter-control Center Communications Protocol (ICCP) message) to a DPNelement of a second distributed private network (e.g., an EMS of asecond electric utility), where the two smaller distributed privatenetworks are components of a larger distributed private network (e.g., aregional or national electrical grid). In such a case, the messagecoordinators of the smaller distributed private networks may providemessage translation, routing, and/or prioritization for purposes ofcommunicating the contents of the received message (e.g., request orinformation) to a target DPN element in the other distributed privatenetwork.

For example, an inter-network interface of a first distributed privatenetwork (e.g., first electric utility) may receive an operations message(e.g., ICCP message) from a message coordinator for a second distributedprivate network (e.g., second electric utility), where the operationsmessage is directed to a target DPN network element (e.g., EMS) withinthe first distributed private network or a target DPN network element(e.g., EMS) within a third distributed private network. The operationsmessage may be a message informing of an updated status, attribute,function, or participation of a DPN network element within the seconddistributed private network (e.g, updated status of a generator in thesecond utility). Additionally, the operations message may include thetransport route and priority for communicating the operations message orits contents to the target DPN network element. In such a case, themessage coordinator for the second distributed private network maycommunicate the operations message or a new, translated version thereof,as applicable and with the appropriate routing and priority, to thepublic communication network that provides packetized message service tothe particular target DPN network element. Alternatively, the messagecoordinator for the second distributed private network may provide theoperations message or a translated version thereof to the messagecoordinator for the target distributed private network (first or third,as applicable) to enable the latter message coordinator to properlyprocess the operations message within its distributed private network.

To further illustrate cross-DPN messaging as supported by thearchitecture of FIG. 2, a DPN network element 221 of a first distributedprivate network sends a packetized message intended for a DPN networkelement 220 of a second distributed private network. The originalmessage is received by the INI element 215 located in the service area203 of the public communication network serving the sending DPN networkelement 221. The INI element 215 communicates the received message tothe message coordinator for the first distributed private network. Themessage coordinator for the first distributed private network determinesthat the message is intended for a DPN network element of a seconddistributed private network and either communicates the message with anassigned priority and transport route to the message coordinator for thesecond distributed private network or translates the message into aformat used in the second distributed private network and communicatesthe translated message, which includes the payload or other criticalcontents of the original message, as well as a priority and a transportroute, to an INI element of the second distributed private network. TheINI element of the second distributed private network communicates thetranslated message or a new message based on the translated message tothe public communication network providing communication service to thetarget DPN network element.

Where the architecture for the inter-network interface is such that theinter-network interface includes multiple INI elements 211, 215 asillustrated in FIG. 2, each INI element may perform limited processingon a received packetized message in order to properly format it fortransmission to the message coordinator for the distributed privatenetwork in which the message was sent or to the DPN network element thatis the target of the message. Therefore, where a first INI element(e.g., INI element 215) receives a packetized message from a DPN networkelement 221, the first INI element forwards the message or a modifiedversion of it (e.g., with modified headers or addressing) to the messagecoordinator 223 for the applicable distributed private network. Themessage coordinator then provides appropriate routing, prioritization,and security functions for the received message, such as by selectingand assigning the appropriate transport route and priority for themessage, as well as adding or authenticating/validating the appropriatesecurity protocol. Where, for example, the security protocol for themessage has been applied by the sending DPN network element 221 (e.g.,through appropriate encryption), the message coordinator 223 for thedistributed private network may validate the security protocol beforerouting the message to the INI element in the service area of the publiccommunication network providing communication service to the target DPNnetwork element (e.g., DPN network element 220). Alternatively, wherethe message received from the sending DPN network element 221 does notinclude the appropriate security protocol for delivery of the message tothe target DPN network element, the message coordinator 223 may add therequired level of security to the message before sending the modifiedmessage to the delivery INI element (e.g., INI element 211). Thetransport route assigned by the message coordinator 223 may be based onthe contents of the message, a priority for the message, or otherfactors as may be programmed into the message coordinator based on therequirements for the particular distributed private network. Forexample, where the distributed private network is a network for anelectrical utility or an electrical grid and the DPN network elementsbetween which the packetized message is to be exchanged are gridelements, the security protocol may be required to comply with the NorthAmerican Electric Reliability Corporation Critical InfrastructureProtection (NERC CIP) standards.

After the message coordinator 223 processes the packetized message, themessage coordinator 223 communicates a new or modified messagecontaining the contents of the original message, a priority, and atransport route to an INI element 211 in the service area 202 containingthe target DPN network element 220. The INI element 211 receives thepacketized message from the message coordinator 223 and, based upon themessage's priority and transport route, either forwards the receivedmessage to the public communication network providing packetized messageservice to the target DPN network element 220 or generates a newpacketized message (e.g., the received message with modified addressing)and communicates the new message to the public communication networkservicing the target DPN network element 211.

FIG. 3 is a block diagram illustrating configuration of a system forcommunicating messages of one or more distributed private networks overmultiple public communication networks operated by correspondingcommunication service providers, in accordance with another exemplaryembodiment of the present disclosure. The system architecture embodimentillustrated in FIG. 3 is similar to the architecture embodimentillustrated in FIG. 2, except that the inter-network interface isimplemented wholly or partially as a cloud service 301 provided by ahost communication service provider (e.g., Service Provider A) or athird party, such as an independent private network message aggregator.

Where the inter-network interface for a particular distributed privatenetwork is implemented as a cloud service 301, the message coordinator223 may also be implemented as part of the cloud service 301 or may bealternatively coupled to the cloud service (e.g., interconnected withthe applicable cloud servers) via appropriate data links. In thisembodiment, the packet router 205 and the distributed INI elements 311,315 are coupled to the cloud service through respective Internet serviceproviders (ISPs). INI elements 311, 315 are similar to INI elements 211,215 of FIG. 2, except that the INI elements 311, 315 of FIG. 3 areinterconnected with the cloud service and may utilize Internet-basedsecurity mechanisms, such as secure socket layer encryption for allcommunications between the INI elements 311, 315 and the cloud service.

FIG. 4 is an electrical block diagram illustrating essential andoptional components of an inter-network interface 401 and a DPN networkelement 403, in accordance with a further exemplary embodiment of thepresent disclosure. The inter-network interface 401 and the DPN networkelement 403 exchange packetized messages over a public communicationnetwork 405 operated by a communication service provider. Theinter-network interface 401 includes, among other things, one or moretransceivers 407, a processing function 409, and memory 411. The memory411 may store executable operating instructions 413 (e.g., an operatingsystem and other computer programs specially configured to performprocesses and functions used by the inter-network interface 401),routing tables 415 for each distributed private network supported by theinter-network interface, one or more prioritization protocols 417 forthe supported distributed private networks, and/or one or more securityprotocols 419 for the supported distributed private networks. Theinter-network interface 401 may optionally include one or morepacketized message points of interface (POIs) 421 and, where theinter-network interface 401 supports VoIP services, one or more VoIPPOIs 423. In one embodiment, the one or more packetized message point ofinterface includes a plurality of packetized message points of interfacelocated within two or more service areas of the plurality of publiccommunication networks. In one embodiment, the one or more packetizedmessage POIs and the VoIP POIs are integrated into a single point ofinterface. Each packetized message POI and each VoIP POI, or each set ofpacketized message POIs and VoIP POIs, may include their own respectiveprocessors 425, 427 or other processing devices or functions.Alternatively, the functions of the POI and/or VoIP POI processors 425,427 may be incorporated in the overall processor function 409 of theinter-network interface 401. The VoIP POI 423 and its associatedprocessor 427 may function to determine do determine at least one ofquantity, sizes, and durations of VoIP messages that pass through theVoIP point of interface during a predefined billing period and whichoriginated from the public communication network operated by the firstcommunication service provider; and report one or more of the determinedquantity, sizes, and durations of VoIP messages to a billing system ofthe first communication service provider to facilitate a periodicdetermination of an amount of funds to be paid by the firstcommunication service provider to a rural telephony service assistancefund under applicable communications regulations.

Additionally, where message coordinator functionality is incorporatedinto the inter-network interface 401, the processing function 409 of theinter-network interface 401 may include message coordinator functionsfor one or more DPN message coordinators 429-431 (three messagecoordinators 429-431 being shown for illustration purposes). When theprocessing function 409 performs a message coordinator function, themessage coordinator function may be stored as computer programinstructions 413 in the memory 411.

The DPN network element 403 may include, among other things, one or moretransceivers 433, a processing function or device 435, and memory 437.The memory 437 preferably stores executable operating instructions 439(e.g., an operating system and other computer programs) speciallyconfigured to perform processes and functions used by the DPN networkelement 403 in the distributed private network of which it is a part.

With reference to the OSI protocol stack 500 conventionally used forInternet communications, which stack 500 is illustrated generally inFIG. 5, the transceivers 407, 433 of the inter-network interface 401 andthe DPN network element 403 preferably process the physical and datalink layers and sublayers 501, 502 of packetized messages communicatedbetween the inter-network interface 401 and the DPN network element 403.The packetized messages are preferably, although not exclusively,communicated using packetized messaging protocols, such as the InternetProtocol suite of message protocols.

Upon receiving a packetized message from the public communicationnetwork 405, the inter-network interface 401 determines whether themessage was communicated by a DPN network element 403. According to oneexemplary embodiment, the processing function 409 of the inter-networkinterface 401 may make such a determination by analyzing the lowerprotocol layers of the received message. Referring to FIG. 5, theprocessing function 409 may process and evaluate one or more of thephysical, data link, network, and transport layers 501-504 of thereceived message to determine whether a messaging format 509 specific toa distributed private network has been used, where the packetizedmessages are constructed in accordance with the OSI protocol stack 500.In one particular embodiment, the DPN-specific messaging format, whenused, may be included in an aggregation sublayer 511 of the transportlayer 504 (layer 4), as discussed in more detail below with respect toFIG. 6. When the DPN-specific messaging format is includes included inthe lowest layers of the protocol stack 500 (e.g., the physical layer501 or the data link layer 502), the processing function 409 may controlthe transceiver 407, as necessary, to examine the details of thoselayers 501, 502 to perform the formatting analysis. By including theDPN-specific messaging format in the lower layers of the protocol stack500, the inter-network interface need not expend processing resources toexamine the higher protocol layers, such as the session layer 505,presentation layer 506, or applications layers 507, which generally havemore extensive processing requirements.

As an example of message data flow that may occur between layers ofprotocol stacks executing within elements of a system for communicatingpacketized messages of a distributed private network over multiplepublic communication networks, reference is made to the exemplary flowsshown in FIG. 6. As illustrated in the figure, a first DPN networkelement (Network Element 1) utilizes a complete OSI protocol stack thatincludes physical, data link, network, transport, session, presentation,and application layers 601-607. The transport layer 604 of the first DPNnetwork element includes an optional aggregation sublayer 608 thatcontains a messaging format to indicate that a packetized messageoriginated by the first DPN network element is a message communicated inthe distributed private network that includes the first DPN networkelement. As discussed above, the DPN-specific messaging format may beincluded one or more other lower layers of the protocol stack, or may beexcluded altogether when the inter-network interface 401 is configuredto determine, using an alternative process (e.g., a lookup table of DPNnetwork element addresses and associated distributed private networks)that a received packetized message has been communicated in adistributed private network.

Similar to the first DPN network element, a second DPN network elementof the distributed private network (Network Element 2) utilizes acomplete OSI protocol stack that includes physical, data link, network,transport, session, presentation, and application layers 631-637. Thetransport layer 634 of the second network element may also include anoptional aggregation sublayer 638 to process the messaging formatcontained in the aggregation sublayer 608 of the message sent by thefirst DPN network element and to contain a DPN-identifying messagingformat for packetized messages generated by the second DPN networkelement. Thus, the protocol stack in each DPN network element of aparticular distributed private network is substantially the same.

In contrast to the protocol stacks of the DPN network elements, theprotocol stack of the inter-network interface 401 used for purposes ofprocessing received packetized messages need not include all of theprotocol layers because, for such purposes, the inter-network interface401 only needs to process the lower protocol layers in order to confirmthat a received message is being communicated in a distributed privatenetwork and to route the message to the appropriate message coordinator.As a result, the protocol stack of the inter-network interface may onlyneed to include the physical layer 611, the data link layer 612, thenetwork layer 613, and the transport layer (or just the aggregationsublayer 618, when the DPN-specific messaging format 509 is includedtherein). For purposes of processing packetized messages received fromthe inter-network interface 401, the message coordinator for thedistributed private network (e.g., message coordinator 429) may alsoonly need the lower layers of the protocol stack (e.g., the physicallayer 621, the data link layer 622, the network layer 623, and thetransport layer (or just the aggregation sublayer 628, when theDPN-specific messaging format 509 is included therein)), depending onhow far up the stack the information is contained to enable the messagecoordinator 429 to perform its prioritization, routing, and/or securityfunctions with respect to the received message. As those of ordinaryskill in the art will readily recognize and appreciate, if the messagecoordinator 429 is also configured to generate or further processmessages in the distributed private network it supports, the messagecoordinator 429 may need to include the entire protocol stack for theparticular distributed private network. However, for purposes ofanalyzing a packetized message originated by a DPN network element, lessprocessing is necessary in the inter-network interface 401, and may benecessary in the message coordinator 429, for purposes of directing themessage to the appropriate public network for delivery to the message'sintended target.

As illustrated in FIG. 6, when the first DPN network element sends apacketized message over a public communication network, the transceiver407 of the inter-network interface 401 receives and processes thephysical and data link layers 601, 602 of the message and forwards themessage to the processing function 409 for further processing. Theprocessing function 409, in accordance with the stored operatinginstructions 413, processes the network layer 603 and aggregationsublayer 608 of the message to determine whether the message is beingcommunicated in a distributed private network. For example, theprocessing function 409 may determine whether the aggregation sublayer608 includes a messaging format indicative of a particular distributedprivate network. When the processing function 409 detects a DPN-specificmessaging format 509 in the aggregation sublayer 608 or another lowerlayer of the message's protocol stack, the processing function 409communicates the message to the message coordinator 429 for theparticular distributed private network. The message coordinator 429 maybe separate from the inter-network interface 401 or may be a functionwithin the inter-network interface 401. Where the message coordinator429 is a process or function within the inter-network interface 401, thecommunication of the message to the message coordinator 429 may bemerely a logical communication between the operating instruction modules413 (program code) implementing the inter-network interface and messagecoordinator functions.

Upon receiving the packetized message from the inter-network interface'sprocessing function 409, the message coordinator 429 processesappropriate layers of the message's protocol stack in order to determinea transport route for the message and an optional priority to beassigned to the message, as well as to optionally confirm that themessage complies with the security protocol for the distributed privatenetwork. Where the message coordinator 429 is integrated in theinter-network interface 401, the processing function 409 of theinter-network interface 401 may implement the message coordinatorfunction and retrieve the appropriate prioritization protocol 417 andsecurity protocol 419 from memory 411 upon determining which distributedprivate network is involved. After analyzing the message, the messagecoordinator 429 may assign a priority and a transport route for themessage. Assignment of the transport route may be a fixed assignment asstored in the routing tables 415, or such an assignment may be based onat least one of (a) a state of the distributed private network at a timewhen the packetized message was received at the inter-network interface401 and (b) at least one of a function and a participation of the targetnetwork element within the distributed private network. For example, thetransport routes stored in the routing tables 415 may be updated fromtime to time to reflect the current status of the distributed privatenetwork and/or the functions and/or participations of the DPN networkelements. The message coordinator 429 may then select the transportroute for the received message from the most recently updated routes inthe routing tables 415. Alternatively, the message coordinator 429 maydetermine a transport route in real time by executing a routingalgorithm that takes into account various parameters, including thestate of the distributed private network at a time when the packetizedmessage was received at the inter-network interface 401 and a functionand/or participation of the target network element within thedistributed private network.

In addition to assigning a transport route, the message coordinator 429may optionally assign a priority to the message based on theprioritization protocol 417 for the distributed private network. Theprioritization protocol may include several levels of priority based onvarious parameters, such as the function and/or participation of thesending and/or target DPN network elements, the type of message, thecurrent state of the distributed private network, the time of day,environmental conditions, a class of service supported by the publiccommunication network providing communication service to the target DPNnetwork element, and so forth. The class of service comprises a class ofInternet service.

The message coordinator 429 may further optionally generate a new securepacketized message directed to the target network element if thereceived message does not comply with the security protocol 419 for thedistributed private network. The new message would include the contentsof the received message and comply with the security protocol 419 forthe distributed private network (e.g., include appropriate encryptionand other security measures to comply with the security protocol of thedistributed private network). Alternatively, if the received messageincludes the proper security protocol, the message coordinator maynevertheless generate a new message that includes the contents of theoriginal message, as well as the assigned priority and transport routeinformation. After assigning the transport route and optional priority,and either verifying security protocol compliance or creating a newsecurity protocol-compliant message, the message coordinator 429communicates the secure packetized message via the transceiver 407 tothe public communication network 405 servicing the target DPN networkelement based upon the priority and the transport route.

In an alternative embodiment in which the inter-network interface 401supports multiple independent and dedicated subnetworks, the processingfunction 409 may be further operable in accordance with the operatinginstructions 413 to assign each distributed private network to its ownsubnetwork. In such a case, messages received on a subnetwork may bereadily identified as being communicated within the distributed privatenetwork assigned to the particular subnetwork.

FIG. 7 is a logic flow diagram 700 of steps executed by an inter-networkinterface 401 to facilitate the communication of messages of one or moredistributed private networks over multiple public communicationnetworks, in accordance with another exemplary embodiment of the presentdisclosure. According to the logic flow reflected in the diagram 700,the inter-network interface 401 receives (701) a packetized message froma public communication network 405. The inter-network interface 401determines (703) whether the received message is directed to a networkelement of a distributed private network. Such a determination may bebased on analyzing the lower protocol layers of the message for aDPN-specific messaging format, comparing the destination address of themessage to a database correlating device addresses with distributedprivate networks, determining a subnetwork on which the message wasreceived, and so forth. If the received message is directed to a networkelement of a distributed private network, the inter-network interface401 may optionally decrypt (705) the message based on the securityprotocol for the distributed private network, although such an actionmay require an undesirable amount of processing resources depending onhow far up the protocol stack the security protocol encryption iscontained.

If the received message is not directed to a network element of adistributed private network, the inter-network interface 401 determines(707) whether the message is a VoIP message. If the message is a VoIPmessage, the inter-network interface 401 adds (709) the message to aquantity, size and/or duration being monitored on behalf of the publiccommunications network from which the message originated for purposes ofperiodically reporting VoIP call data to the public network's billingsystem to compute the network's regulatory payment into the USF fund oranother rural telephony service assistance fund under applicablecommunications regulations.

If the received message is not a VoIP message and was directed to a DPNnetwork element, the inter-network interface sends (711) the message toa message coordinator for the involved distributed private network.Thereafter, the inter-network interface may receive (713) a modifiedmessage from the message coordinator, which may include a priority and atransport route for the message. The inter-network interfacecommunicates (715) the message received from the message coordinator tothe public communication network providing data service to the targetDPN network element based on the priority and transport route.

FIG. 8 illustrates a logic flow diagram 800 of steps executed byelements of a system for communicating messages of one or moredistributed private networks over multiple public communicationnetworks, in accordance with a further exemplary embodiment of thepresent disclosure. According to the logic flow of FIG. 8, a DPN networkelement generates (801) raw data based on a function and/or aparticipation of the DPN network element in the particular distributedprivate network. The DPN network element may then transform (803) theraw data into data usable by one or more other elements of thedistributed private network. For example, where the DPN network elementis a smart meter and accompanying processor programmed to producerevenue grade metrology data, the smart meter may measure the raw datarelating to power consumed at a location and the processor may transformthe raw data into revenue grade data through use of an appropriatealgorithm.

The DPN network element generates (805) a packetized message containingthe transformed data based on the requirements (including securityrequirements) of the distributed private network and transmits (807) thegenerated message over a lower class of service public communicationnetwork. According to this embodiment, the DPN network element ispresumed to be located in a service area of a rural or lower classpublic network.

The transmitted message is received (809) at an inter-network interfaceoperated by a higher class of service communication service provider.For example, the higher class of service provider, such as a commercialcable, wireline, or wireless carrier, may control the inter-networkinterface, which may include multiple inter-network interface (INI)elements distributed within service areas or boundaries of lower classof service carriers. In such a case, an INI element located in a servicearea of a lower class of service carrier providing communication serviceto the DPN network element may have received the original packetizedmessage from the DPN network element.

Upon receiving the message at the inter-network interface, theinter-network interface determines (811) whether the message is a VoIPmessage. If the message is a VoIP message, the inter-network interface401 adds (813) the message to a quantity, size and/or duration beingmonitored on behalf of the public communications network from which themessage was received for purposes of periodically reporting VoIP calldata to the public network's billing system. Based on the periodicreporting, the public network's billing system may compute the network'sregulatory payment into the USF fund or another rural telephony serviceassistance fund under applicable communications regulations.

If the received message is not a VoIP message and was directed to a DPNnetwork element, the inter-network interface sends (815) the message toa message coordinator for the involved distributed private network. Themessage coordinator then assigns (817) a transport route and optionalpriority to the message, and maintains the security requirements for thedistributed private network. As discussed above, maintaining suchsecurity requirements and/or assigning the transport route and/orpriority may involve generating a new message containing the transportroute and priority, and encrypting the new message to comply with thesecurity protocol of the distributed private network. After thetransport route and optional priority have been assigned, the messagecoordinator communicates (819) the original, modified original, or newmessage, via the inter-network interface, to a lower class of servicepublic communication network providing packetized data service to thetarget DPN network element based on the assigned priority and/ortransport route. The public communication network providing packetizeddata service to the target DPN network element may be the same networkproviding packetized data service to the sending DPN network element oranother public communication network (e.g., as serviced by another ruralor lower class of service carrier).

Certain modifications and improvements will occur to those skilled inthe art upon a reading of the foregoing description. By way of exampleand not limitation, the present invention systems and methods areapplicable to electric power grid communications, and to communicationsfor any critical infrastructure, for public safety, for oil and gasnetworks, etc. The above-mentioned examples are provided to serve thepurpose of clarifying the aspects of the invention and it will beapparent to one skilled in the art that they do not serve to limit thescope of the invention. All modifications and improvements have beendeleted herein for the sake of conciseness and readability but areproperly within the scope of the present invention.

What is claimed is:
 1. A system for communicating messages of adistributed private network (DPN) over a plurality of communicationnetworks for critical infrastructure, the system comprising: at leastone of an inter-network interface and a message coordinator; wherein theinter-network interface comprises at least one network interface, aprocessing function and a memory; and wherein the message coordinatorcomprises at least one network interface, a processing device and amemory; wherein the inter-network interface is part of a service area ofa first electric utility; wherein the inter-network interface iscommunicatively coupled to the message coordinator; wherein theinter-network interface is operable to receive a packetized message froma first DPN network element of the service area of the first electricutility over a first communication network; wherein the packetizedmessage utilizes a complete Open Systems Interconnection (OSI) protocolstack, including physical, data link, network, transport with anaggregation sublayer, session, presentation, and application layers,wherein the protocol stack identifies the packetized message as being amessage communicated within the DPN; wherein the inter-network interfaceis operable to process the packetized message from lowest to highest OSIlayer using only physical, data link, network, and transport layers withaggregation sublayer; wherein the inter-network interface is operable tocommunicate the packetized message to the message coordinator; whereinthe message coordinator is operable to: receive the packetized messagefrom the inter-network interface; assign a transport route for thepacketized message; assign a priority and a security protocol to thepacketized message based on a prioritization protocol for the DPN,wherein the prioritization protocol is based on a class of service to asecond DPN network element of a second service area of a second electricutility; and return the packetized message to the inter-networkinterface; wherein the inter-network interface is operable to determinewhether the assigned transport route is available; wherein theinter-network interface is operable to communicate the packetizedmessage to the second DPN network element over a second communicationnetwork based on the assigned transport route or an alternativetransport route when the assigned transport route is unavailable; andwherein the first DPN network element has a lower class of service thanthe inter-network interface.
 2. The system of claim 1, wherein theprioritization protocol further includes several levels of prioritybased on various parameters including a function and/or participation ofthe first and second DPN network elements, a type of the packetizedmessage, a current state of the DPN, a time of day, or environmentalconditions.
 3. The system of claim 1, wherein the inter-networkinterface is controlled by a first communication server provider or anindependent private network message aggregator; wherein the firstcommunication network is operated by a second communication serviceprovider; and wherein the second communication network is operated by athird communication service provider.
 4. The system of claim 1, whereinthe inter-network interface further comprises at least one packetizedmessage point of interface.
 5. The system of claim 1, wherein theinter-network interface further comprises at least one Voice overInternet Protocol (VoIP) point of interface for supporting VoIPservices.
 6. The system of claim 5, wherein the at least one VoIP pointof interface is operable to determine whether the packetized message isa VoIP message and add the determined VoIP message to a quantity, size,and/or duration for periodically reporting VoIP call data to a billingsystem of the first communication network.
 7. The system of claim 6,wherein the billing system of the first communication network isoperable to compute a regulatory payment of the first communicationnetwork into a USF fund or another rural telephony service assistancefund under applicable communications regulations.
 8. The system of claim1, wherein the inter-network interface includes the message coordinator.9. The system of claim 1, wherein the message coordinator and theinter-network interface are co-located.
 10. The system of claim 1,wherein at least one of the inter-network interface and the messagecoordinator is implemented at least partially as a cloud-based service.11. The system of claim 1, wherein the DPN is a large composite DPNincluding multiple subnetworks, wherein the inter-network interface isoperable to support multiple independent and dictated subnetworks basedon prioritization and security requirements of each of a multiplicity ofsupported DPNs.
 12. The system of claim 1, wherein assignment of thetransport route is a fixed assignment as stored in routing tables storedin the memory of the inter-network interface.
 13. The system of claim 1,wherein assignment of the transport route is based on at least one of(a) a state of the DPN at a time when the packetized message is receivedat the inter-network interface and (b) at least one of a function and aparticipation of the second DPN network element within the DPN.
 14. Thesystem of claim 1, wherein the first DPN network element is in a firstDPN and the second DPN network element is in a second distributedprivate network.
 15. A method for communicating messages of adistributed private network (DPN) over a plurality of publiccommunication networks, comprising: providing an inter-network interfaceof a first service area communicatively coupled to a messagecoordinator; a first DPN network element of a first service areagenerating raw data based on a participation in the DPN and transformingthe raw data into revenue grade data; the inter-network interfacereceiving a packetized message from the first DPN network element over afirst public communication network, wherein the packetized messageincludes the revenue grade data; wherein the first DPN network elementhas a lower class of service than the inter-network interface; whereinthe packetized message utilizes a complete Open Systems interconnection(OSI) protocol stack, including physical, data link, network, transportwith an aggregation sublayer, session, presentation, and applicationlayers, wherein the protocol stack identifies the packetized message asbeing a message communicated within the DPN; the inter-network interfaceprocessing the packetized message from lowest to highest OSI layer usingonly physical, data link, network, and transport layers with aggregationsublayer; the inter-network interface communicating the packetizedmessage to the message coordinator; the message coordinator receivingthe packetized message from the inter-network interface; the messagecoordinator assigning a transport route for the packetized message; themessage coordinator further assigning a priority and a security protocolto the packetized message based on a prioritization protocol for theDPN, wherein the prioritization protocol is based on a class of serviceto the second DPN network element; the message coordinator returning thepacketized message to the inter-network interface; the inter-workinterface communicating the packetized message to a second DPN networkelement of a second service area based on the assigned transport routeover a second public communication network.
 16. The method of claim 15,wherein the prioritization protocol includes several levels of prioritybased on various parameters including a function and/or participation ofthe first and second DPN network elements, a type of the packetizedmessage, a current state of the DPN, a time of day, and/or environmentalconditions.
 17. The method of claim 15, further comprising theinter-network interface determining whether the packetized message is aVoice over IP (VoIP) message and adding the VoIP message to a quantity,size, and/or duration for periodically reporting VoIP call data to abilling system of the first public communication network.
 18. The methodof claim 17, further comprising the inter-network interfacecommunicating the packetized message to the message coordinator if thepacketized message is determined not to be a VoIP message.